


Kinktober 2018

by Magyka13



Category: Undertale (Video Game)
Genre: Against A Wall/Furniture, Biting, Blood Drinking/Vampirism, Bondage, Bukkake, Consensual Somnophilia, Costume, Creampie, Cum Inflation, Double (or more) Penetration, F/F, F/M, Face-Sitting, Fucking Machine, Glory Hole, Kinktober 2018, M/M, Macro/Micro, Mirror Sex, Multi, Other, Praise-Kink, Roleplay, Sensory Deprivation, Shower/Bath, Sixty-nine, Size Difference, Skull Fucking, Tentacles, Threesome (or more), Uniforms, collaring, cross-dressing, heat - Freeform, primal play, public
Language: English
Status: In-Progress
Published: 2018-10-07
Updated: 2018-10-11
Packaged: 2019-07-27 17:28:01
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 30
Words: 15,581
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16223861
Author URL: https://archiveofourown.org/users/Magyka13/pseuds/Magyka13
Summary: Or just another reason to whore out my own Sans, Occulttale Sans aka Runix





	1. Day 1: Cum Inflation

**Author's Note:**

> Runix x Red  
> RedRunes
> 
> I'm going to try and stick to around 500-word drabbles

Red grunts as he grasps Runix' summoned hips, careful not to dig his claws too hard into the sensitive ecto-flesh not wanting to scar up his mate any more than he already is scarred. "Stars Rune look at how swollen yer stomach has gotten from my cum" Red growls out, his voice somehow deeper and more arousing than usual as he rubs Runix' swollen stomach. Runix moans weakly, barely able to lift his head from the pillows to give Red a proper reply other than his heavier breathing and breathy moans.

 

Red chuckles at Runix' response, thrusting hard earning himself another drawn-out moan from his mate. "Ya ready for more, Runie?" Red growls out as he feels himself get closer as Runix' entrance clenches around him his tails quivering at his side. With a muffled moan, Runix cums clenching around Red who curses thrusting hard enough to knock Runix over cumming deep within him making his swollen ecto-stomach strain.

 

Pulling out with a soft groan, he wraps his mate in his arms marveling at how swollen Runix' stomach had gotten as he rubs a hand over it. "You took it so well, babe" Red whispers, kissing the side of Runix' skull. "Heh, it's so full" Runix murmurs, placing his hand within Reds hand that is resting on his stomach. He begins turning to look at Red, his eye sockets drifting slowly closed. Red chuckles, nuzzling his skull against Runix' when Red realizes he had worn the other out as soft snores greet him.

 

Chuckling, Red carefully gets up careful not to wake Runix. Going to the adjoining bathroom he returns with a damp warm rag. Ever so slowly, Red wipes Runix clean making sure not to snag the cloth on the various chips and old scars his mate had acquired over too many to count resets in his own universe. Since Runix had arrived, Red could knot deny he had been enamoured with the skelekitsune since he first laid eyes on the slightly smaller being. 

 

Runix had arrived in their smashed together universe; Fell, Swap and Tale after a failed reset of his own. Everyone had been understandably shaken after they found out exactly how the slightly smaller skelekitsune had triggered said reset. At least then the scars on Runix' arms had made sense after they were told the story behind them. Not that they'd let him add to those particular scars, just that they now knew why they were there.

 

Red chuckles softly, thinking back fondly on how he had first met Runix, trying to avoid thinking of how broken the other was when he had first gotten there. Cleaning himself off when he returns to the bathroom, Red returns to the room with the softest blanket they owned in his arms. Chuckling at how Runix had curled up much like a cat in his sleep, Red joins him. Kissing the top of Runix' skull, Red pulls the covers over the two of them and pulls Runix closer falling to sleep with him in his arms.


	2. Day 2: Heat (Bonus first time)

**Summary for the Chapter:**

> Heat
> 
> Runix x Blue aka Underswap Sans

"Runix?" Blue calls as he slowly opens the door to the darkened room. The others had told him that Runix had locked himself in his room all day. Even at the promise of bottles upon bottles of specially made ketchup or anything and the others were understandably worried. They hadn't been able to get inside long enough to see if Runix was ok before being forcefully shoved out of the room by magyk.

 

"B-blue? Y-you shouldn't bee here." Runix mumbles from somewhere in the darkened room as Blue shuts the door behind him, already having gotten further than the others, somehow. Though Blue knew it had something to do with the crush the skelekistune had on him. 

 

"I'm right here Runie can you tell me what's wrong?" Blue asks, worried about the other. It wasn't too uncommon for Runix to get in rather dark moods unable to stop from isolating himself. All they could do in those times was make sure he knew they were there for him and try not to crowd him.

 

"I don't...I don't know...I feel so warm...it hurts." Runix tells him and Blue can hear the pain that he's trying to hide. Runix barely showed pain in anything having been hurt rather badly in his own au both mentally and physically so for him to hint at the pain in his voice signified significant harm. The realization of this sends Blue on high alert, looking around for the light switch to help him find his wayward friend.

 

"Runix? I need to turn the light on. Can you ease up on the darkness a little?" Blue asks the other, sighing in relief as the darkness lightens. Immediately he flips the light on flinching as the room brightens taking in the sight of the room. The room is a mess, clothes, and bedsheets thrown everywhere. As Blue looks around the room he spots Runix under a thin sheet on the bed sweat pouring down his shaking frame the fur on his ears and the parts of his tails peeking out of the sheet plastered to the 'skin'.

 

"Oh, stars Runie are you ok?" Blue asks, rushing to Runix' side surprised as the smell of moonflowers smacks him in the face. Oh. That's what's going on. "Runie do you know what a heat is?" Blue asks earning him a small shake of Runix' head indicating no. "Well, it's a time when a monster needs to seek a partner to *ahem* ride it through as it makes them crave, well, need sex," Blue explains watching as realization dawns on Runix' skull along with shame and fear.

 

Quickly approaching Runix and grounding him with a deep kiss, Blue glows with joy as Runix all but melts against him. "Let me help you, we can talk about other things later. Right now helping you through this is more important." Blue whispers to Runix as he breaks the kiss (regretfully, that cute little mouth was delicious). "Let me show you a great thyme" Blue whispers as he pulls Runix to him, his hands roaming Runix' shaking form.


	3. Day 3: Sensory Deprivation

**Summary for the Chapter:**

> Sensory Deprivation
> 
> Dust x Runix

"You ready Rune?" Dust asks as Runix makes himself comfortable laying down on the soft bed they shared with the others. Since Runix had joined their little group they each had been able to have some special fun time alone with him to avoid overwhelming their newest with too many sensations at once. Dust had wanted to try sensory deprivation and Runix seemed more than willing to comply. The amount of trust Runix is placing in Dusts hands sends shivers down his spine as Runix nods, closing his eye sockets.

 

"Let's start." Dust says as he approaches, gently tying a blindfold to Runix making sure he can't see past the soft velvety cloth covering his eye sockets. Taking a moment to admire Runix' naked pliant form, Dust grabs the 'ear' muffs designed with a particular skeleton in mind and places them on Runix' skull. Now Runix couldn't see or hear him.

 

Dust paces around Runix a few times before placing a hand along Runix' sternum earning him a shuddery breath as Runix jolts relaxing as he recognizes Dust's touch. Chuckling at Runix' reaction he removes his hand earning him a soft whine as he moves it lower, barely teasing Runix' pelvis. He can feel the anticipation in Runix' bones his magyk rising just beneath the surface to form whatever Dust wanted him to form.

 

Dust slowly coaxes Runix' magyk to form a full lower half, plump thighs leading up to a lovely ass, wide hips, and a decent sized member. Taking a moment to admire the shimmering sapphire color of Runix' formed magyk noticing the small spots of red scattered just barely there in the expanse of sapphire color. Grasping Runix' member earns him a gasping moan that he smiles widely at hearing. "You're doing so well Rune" Dust mumbles, not that Runix can hear or see him as he lets go of Runix' member gaining another soft whine. A soft sheen of magykal sweat has collected on Runix' heavily scarred bones from Dust's attention.

 

Turning his attention to watching Runix shiver and gasp from every touch Dust works his mate into a blitzed out mess making sure to avoid touching his member or getting too close to his puckered hole. Chuckling at the arousing sight of his mate all breathy moans and sweaty bones/fur. Dust grabs Runix' member once more giving him a slow but firm few pumps before Runix comes undone beneath him cumming hard enough to completely drench his hand in release.

 

Dust slowly removes the blindfold and earmuffs letting Runix watch as he cleans off Runix' cum from his hand with his tongue. "I'll bee right back" Dust whispers, kissing Runix' skull as he gets the warm rag. Dust hums softly as he gently washes Runix off. Runix gazes sleepily up at Dust, who joins him in bed pulling him to Dust as the two drift off unaware of the tentacle that quietly closes the door, soft snores coming from the Runix as Dust himself slowly drifts off as well.


	4. Day 4: Mirror Sex

**Summary for the Chapter:**

> Mirror Sex
> 
> Outertale Sans aka Outer x Runix
> 
>  
> 
> I probably fucked this one up tbh

"I have a sur-prize for you Runix" Outer greets as he enters the room they both share since Runix had stuttered out his feelings for the other months ago. Papyrus was away for the night with his own date mates, Starby and Starlette so they had the whole house to themselves. "You have to leave the room for a bit so I can set it up ok?" Outer teases, kissing Runix lightly on the top of his skull right between his fluffy white fox ears.

 

"Heh, ok Outer" Runix chuckles, leaving the room with little a sound. It still amazes Outer to this day how Runix is able to walk around almost completely silently without meaning to. Smiling gently as the door closes, Outer sets up the mirrors, one above their four poster bed and one sitting against the closest wall next to their bed. When he decides that they are secure and covered enough for the reveal later, Outer calls Runix back in.

 

"You can come back in now Rune!" Outer calls, knowing the other went to get snacks probably thinking they were going to watch a movie or something. Runix returns with a tray of finger foods and bottles of water floating behind him which he immediately sets on the bedside table. "Good good." Outer comments as he settles himself on the bed, pulling Runix to him still standing. "Get undressed for me will ya?" Outer requests, slowly shrugging off his signature coat.

 

Watching as Runix gets undressed revealing his numerous scars on his bones, Outer touches lightly to the one on Runix' neck earning him a slight shiver. "Come to the bed love" Outer whispers against Runix' ear, stepping back and sitting on the bed waiting. Runix doesn't disappoint as he joins Outer shortly. Kissing Runix deeply, Outer's hands roam Runix' form coaxing his magyk to form his usual lower half his tails twitching. Forming his own almost galaxy looking lower half, Outer reaches around and teases Runix' ass kneading the soft ecto-flesh in his hands.

 

Runix moans softly, allowing himself to be moved into Outers lap facing his mate. After a bit of lining himself up, Outer lowers Runix onto his member both of them moaning softly as Runix slowly seats himself on it.

 

"L-look up," Outer tells Runix, removing the cover to the mirror with blue magyk. Runix noticeably flushes deeper, still somewhat ashamed of his own body despite everything Outer has done to prove to him that he's amazing. "Look Runix, look how I make your stomach bulge." Outer purrs, rubbing Runix' stomach causing the other to moan softly his eye lights gaining that hazy look that Outer loved when he caused. Laying Runix on his back staying inside Outer makes a few test thrusts watching the pleasure flash on his mates face. "Watch Runix, watch in the mirror as I make sweet sweet love to you" Outer commands, punctuating his words with a deep thrust gaining a sharp moan from Runix as Runix struggles to, but manages to keep his gaze on the mirror above him. They could get to the one beside the bed another time.


	5. Day 5: Face-Sitting

**Summary for the Chapter:**

> Face-Sitting
> 
> Horror x Runix
> 
> Feel a little bit better about this one
> 
> a little

"C'mere Runie" Horror growls almost sounding like a purr as he lays on the large bed they all share with Runix, it is his turn to have fun with the skelekitsune by themselves. Runix complies shyly, bare except for the fact his tails are wrapped around his pelvis hiding it like some sort of skirt which somehow made the sight even more arousing for Horror.

 

"S-sure" Runix stutters as he makes his way to the bed where Horror is laying, his head propped up by his pillow.

 

"Come to sit on my chest," Horror tells him, Runix complying as he climbs onto the bed and makes his way to sit on Horrors broad sternum. He looks down at Horror, blushing deeply his signature sapphire color.

 

"W-what is it Horror?" Runix asks, twiddling his phalanges out of habit as he looks down at the downright sinful look Horror is leveling him with. Horror smirks at this adorable look wondering how exactly Error found this little gem among the many countless au's in the multiverse. Taking his hands, he lays them on Runix' hips.

 

"Stop hiding pet, I want to see yer beautiful pelvis." Horror commands gently unwrapping Runix' tails from his pelvis slowly revealing the delicious sight of Runix' hardened member and plump ass. Grasping Runix' hips Horror scoots Runix closer to his skull, licking the tip of Runix' member as he gets close enough. Runix lets out a ragged moan as Horror licks his tip, resisting the urge to thrust forward into his rather inviting mouth.

 

Horrors one eye light drinks in the sight of Runix coming undone on top of him as he takes his member fully in his mouth sucking lightly kneading Runix' soft ass with his hands as he does so. Horror pushes Runix further into his mouth, getting enjoyment on how Runix uses the headboard to brtase himself as moans fall from his open mouth. Using his long tongue to do most of the work, Horror watches in awe as Runix' expressions change from pleasured to blitzed the closer he gets, drool slowly dripping down his skull looking downright delicious as his eye lights turn into sapphire hearts, Horror mirroring with his own red hearts.

 

Grunting as he removes one hand from Runix' hips, Horror grasps his own girthy member out of his pants, stroking it in time as he feels Runix get closer and closer to release wanting to cum with his smaller mate. Runix lets out a choked moan as he cums his cum tasting of berries causing Horror to squeeze particularly hard on his own member cumming on Runix' back coating it in his red cum. Pulling Runix off of his face he lays Runix on his stomach as he cleans the both of them off. Runix snuggles up to him having dozed off shortly after his rather intense orgasm Horror watching the rise and fall of Runix' ribs with a small smile on his face catching a glimpse of Nightmare passing the partially open door, closing it as he passes.


	6. Day 6: Biting

**Summary for the Chapter:**

> Biting
> 
> Red x Runix
> 
> Cuz ya know, Reds fangs that's why

Runix moans deeply as Red thrusts hard, hitting a particularly sensitive spot his eye lights transforming into little blue hearts that if one pays enough attention to have little red dots in the center of them. Wrapping his legs around Reds waist, Runix pulls him deeper loving the feeling of being so full with his mate. He shudders as a thought comes to the front of his head, putting a hand on Reds chest stopping his mate. While he really wanted Red to continue to pound him into the mattress, he really wanted this.

 

"R-red?" Runix asks as they stare into each others eye lights, Red buried deep in his slightly smaller mate. Red stills, worried for a few seconds that he had hurt Runix or something was wrong. Red studies Runix' eye lights determining that something wrong is not the case and Runix simply wants to ask him something.

 

"Y-yeah Runie?" Red asks, his breathing heavier than usual as he feels Runix' insides tremble and quiver around his member. Stars he loves how Runix looks all aroused and flustered at the same time. It's one of the most arousing things Red swears he has seen in his life.

 

"Can...can you mark me? L-like ya know, bite my neck and leave a mark?" Runix asks, nervous and sweaty wanting Red to move but also wanting Red to do that as well.

 

"Ya sure, ya want me ta do this, doll face? I mean it'll hurt a little, they are rather jagged after all." Red mumbles after Runix finishes saying his request mid-coitus. At Runix' nod, Red kisses him deeply before breathing in his scent burying his nose aperture into Runix' neck. Runix gets the message and tilts his head giving Red more access to his neck. Red makes small thrusts as he licks, nips and suckles on Runix' neck to get him ready for his sharp fangs.

 

Runix moans bucking against Red as he begins nipping at his neck, Reds member brushing against every sensitive spot he has causing breathy moans and pleads to fall from his open mouth. Coating his fangs with his intent, Red bites down hard drawing marrow and a rather strangled moan from Runix as he cums hard his entrance clenching around Reds member. 

 

Lapping the marrow up, Red thrusts hard cumming deep within Runix as he watches fascinated as the bite mark shifts to make a glowing pentacle on Runix' neck. Red inspects his marking as it is glowing with the same color and feel of his magyk. Pulling out gently, Red clutches Runix close to him breathing in his unique scent, which is of a flower called a moonflower or morning glory as some call them.

 

Runix shudders as Red pulls out, purring contently as he feels Reds magyk and intent in his neck knowing that he'll always feel Red close even when he's not. Most likely the mark will last even after Reds natural life cycle does. Doing his best not to think about that particular thought, Runix uses his magyk to clean them up. Using his magyk to pull the blankets around them he drifts off in his mates embrace lulled asleep by Reds deep snores.


	7. Day 7: Praise Kink

**Summary for the Chapter:**

> Praise Kink
> 
> Outer x Runix
> 
> Cuz why knot, heh

"You look so amazing Rune" Outer all but purrs, taking in the sight of Runix all flustered standing at the doorway to their shared bedroom his magyk summoned into a full lower half. Runix' legs go up to thick thighs and a round plump ass, a little bit larger than usual for his size member onto a slight pudge of a stomach stopping at his lowest ribs. 

 

"It's a shame I can't tease all of your spine like this but it is worth it for sure" Outer praises, smiling wider as Runix blushes even deeper. "Come here lovely." Outer calls over to Runix as he sits on the edge of the bed motioning for Runix to join him. Runix slowly makes his way over shyly either unaware or unwilling to admit how the slow shy walk accentuates his plump gorgeousness.

 

"How did I get so lucky to find such a gorgeous mate such as you?" Outer asks as Runix gets to him pulling Runix in his lap sideways so he can clearly see the curve in Runix' spine to where his tails connect to the rest of him. "I love how sensitive the base of your tails are" Outer whispers against Runix' ear as he grabs the base of Runix' tails earning him a wheezing moan as Runix arches his back his tails wriggling against Outers arm.

 

"I love how open your expressions are when lost in the pleasure that only I provide you" Outer continues, trailing his hand from the base of Runix' tails to tease at his hole. "Would you like me to continue?" Outer asks. Watching and seeing a nod from the blushing skelekitsune in his lap he slips a phalange in Runix' hole, said Runix moaning quietly at the feel of Outers phalange thrusting in his hole.

 

"Go lay down on the bed on your side" Outer commands, pulling his phalange out and lightly smacking Runix' ass. Runix complies laying on his side watching and waiting on Outer. Outer hands a pillow to Runix to prop his head up as he sits at Runix' ass. His hands roam Runix' form praises falling from his mouth as he feels every dip and curves in Runix' form.

 

Lifting one of Runix' legs he places it on his shoulder, getting on his knees between Runix' legs slowly thrusting in Runix' tight ass moaning at the feeling. "Stars above Rune you're so tight. I love how you squeeze me when I'm making sweet love to you, how your expressions are so open and trusting" Outer moans out as he slowly moves inside Runix. One of his hands roams down and grasps Runix' member pumping in time with his thrusts enjoying the sound of Runix moaning beneath him.

 

It doesn't take long for them to climax, Outer cursing softly as Runix' insides milk his member for all it's worth. Pulling out gently Outer cleans them up pulling Runix into his lap. "You took me so well Rune, I love how gorgeous you look when I'm going to town on you or making sweet love to you" Outer purrs in Runix' ear kissing him lovingly letting Runix feel just how much he loves his mate.


	8. Day 8: Tentacles

**Summary for the Chapter:**

> Tentacles
> 
> Nightmare X Runix
> 
> Who else but Nightmare
> 
> the resident tentacle skeleton

"Y-you wanted to see me Nightmare?" Runix stutters as he enters the bedroom he now shares with the others, fiddling with his phalanges as he approaches Nightmare sitting in the middle of the bed back against the headboard his tentacles moving as if of separate minds. Nightmare motions for Runix to approach, not glancing up from the paperwork he's looking at as Runix approaches and climbs up on the bed settling next to Nightmare.

 

Nightmare sets the paperwork aside, turning to look at Runix who is staring at his lap fiddling with his phalanges. "I wanted to see you because I wanted to have my alone time with you." Nightmare says simply, his tentacles moving Runix to sit facing him in his lap. Runix blushes at the implications, his tails brushing against the smooth texture of Nightmares tentacles. Nightmare, smirks as there are only four of them at the moment. In truth, he could have as many as he wanted out but he didn't want to frighten his newest addition so soon for a reason he couldn't pin.

 

Letting his tentacles wrap around Runix' smaller frame, Nightmare turns Runix' head to look at him kissing the other deeply. Runix' bones are dusted with a shimmery sapphire color as Nightmares tentacles make short work of Runix' many layers of clothes revealing the heavily scarred bones before. Nightmare wasn't surprised as he had seen the many scars before and was used to the sight. Taking a quick look over to see if there are any newer ones or any freshly opened, Nightmare places a hand under Runix' chin.

 

"Safeword is Xio." is all Nightmare says before claiming Runix' mouth once more. Reacting to his thoughts and wants his tentacles caress every bone on Runix teasing sensitive spots and learning newer ones drawing muffled moans from Runix. Pulling from the kiss leaving them connected by a line of blue drool, Runix breathing heavily. "Let it form, I won't judge" Nightmare whispers as one of his tentacles teases the base of Runix' tails. Runix' lower half forms with a soft pop, Nightmare taking a moment to appreciate the color before his tentacles wrap around Runix feeling every dip and curve. One teases Runix' entrance earning a stifled moan.

 

"Don't hide it, I want to hear you" Nightmare whispers as the tentacle moves deeper, thrusting slowly gaining speed as Runix lets loose another moan this time louder as he shudders under Nightmares tentacles menstruations.

 

"A-ah Nnnggg! Nightmare!" Runix calls out, clenching around Nightmares tentacle as he ever so lewdly comes undone in Nightmares lap. Nightmare smirks at the power he feels about making a being with such lv and power writhe under his care, his tentacle swelling with a sort of release the closer Runix gets to his own. With a strangled cry of Nightmares name, Runix cums, his hazy eye lights small hearts. Nightmare growls, holding Runix close as he cums within his newest slowly pulling his tentacle out, deep blue cum dribbling from Runix' hole. Runix passes out against Nightmare, curling against him as Nightmare uses his tentacles to clean Runix holding him in his lap as the smaller sleeps.


	9. Day 9: Bondage

**Summary for the Chapter:**

> Bondage
> 
> Cross x Runix
> 
> Of course right? Yeah.

Runix shudders as Cross levels him with a heated look as he lays on the bed passively his clothes off and magyk summoned, his member hardened resisting the urge to hide his pelvis with his tails. "You'll look so nice all strapped to this bed waiting and ready for me" Cross comments as he makes one more pass around the foot of the bed with the soft furry handcuffs in his hands the fur matching the fur color of Runix' own fur.

 

"C-cross" Runix stutters as Cross gently grasps his left hand in his own attaching the handcuff before attaching the other end to his other wrist attaching both to the headboard above Runix' head. Cross leaves Runix' legs free for now simply letting his hands roam Runix' extremely scarred form. Runix moans as Cross' exploring hands brush against his deeper scars on the underside of his arms near his wrists, his one across his neck and the largest scar going across his sternum from genocide runs.

 

"So lewd" Cross all but growls at Runix, a telltale purple glow coming from his shorts telling Runix just how turned on Cross was by all this. Tugging his own clothes off almost binding himself in the process, Cross takes Runix' ankles and binds each one to the bed leaving enough room for Runix to lift his pelvis some and be able to bend his knees marginally. "So gorgeous all spread out like this for me. Like I've got my own little feast to enjoy" Cross whispers just loud enough for Runix to hear.

 

Runix keens softly as he feels Cross' hand caressing his inner thigh as Cross gets on the bed settling himself between Runix' spread legs. "Hmmm" Cross mumbles, eyeing Runix his mismatched eye lights heart shaped as he eye fucks Runix taking in the sight of him pinned to the bed. Stopping at Runix' tails he takes the straps from his complicated outfit and pins Runix' tails to his legs one for each leg.

 

Ever so slowly, Cross lifts Runix' pelvis lining his deep purple member up with Runix' entrance slowly sinking into the tight heat. "Stars Rune yer as tight as the first time, even with all of us making sweet love to you" Cross swears, hilting fully deep inside Runix' entrance. "Safe word?" Cross asks, stilling completely.

 

"X-xio" Runix pants out wanting Cross to just move already.

 

Cross leans over Runix thrusting slowly but gaining speed hitting hard and deep earning him gasping breathy moans from Runix who wants to wrap his arms and legs around Cross but unable to due to the binds. "I bet you want to wrap those sinful legs around me huh?" Cross asks, his voice deeper than usual from arousal. "That's too bad" Cross tutts, kissing Runix deeply one hand going between them slowly pumping Runix' hardened member offsetting his thrusts with the slow pace.

 

"Aghkk C-cross!" Runix cries out as he cums, Cross following shortly after with a muffled curse. Pulling out slowly, Cross unties Runix chuckling softly as Runix clings to him wanting to cuddle in the post-sex haze. He complies, wrapping his arms around the only one shorter than him and Dust ignoring how his cum slowly dribbles out of Runix' entrance.


	10. Day 10: Micro/Macro

**Summary for the Chapter:**

> Micro/Macro
> 
> Sans X Runix
> 
> Were ya expecting someone else, kiddo?
> 
> It's a classic

"S-sans? Are you there? I need a bit of help." Runix calls, walking across the much larger dresser having accidentally turned himself about as small as a cat nervous about jumping off the high dresser to get to the floor. Runix yelps as Sans stands suddenly, being much taller now than the now very much shrunk Runix and since it is because of a potion he can't seem to transform to his usual height, which while would still be shorter than Sans, it wouldn't be by this much.

 

"You okay Runix?" Sans asks, looking at where Runix is perched on top of the dresser. He's a little larger than usual due to another potion mishap that Runix had been trying to solve but Sans had startled the skelekitsune making him douse himself in the whole bottle of potion. "Heh, seeing you this small gives me an idea," Sans whispers, picking Runix up and holding him in his hands.

 

"W-what is the idea you h-" Runix cuts off as Sans licks his entire face with his large tongue. "Oh," Runix says blankly staring up at Sans trying to let his brain process what the other just hinted at. Sans gets impatient for once at his lovers seemingly fried brain and makes short work of the smaller clothes.

 

"W-wha-" Runix cuts off with a moan as Sans licks his pelvis, his magyk stirring in his bones.

 

"Let's see how much bigger my phalanges are with you this much smaller than I shall we?" Sans whispers his voice sending shivers down Runix' spine. Sans manipulates Runix in his hands so that he's laying across it, his head resting on Sans' thumb while his pelvis almost dangles off the side his legs actually doing so.

 

"S-sans..." Runix murmers, looking up at Sans who stares back both of their eye lights little hearts. With an almost inaudible pop, Runix' magyk summons his member hard and ready. Sans gives him one last hungry look before raising Runix to his mouth his tongue teasing his entrance.

 

Runix lets out a strangled moan as Sans' tongue explores his entrance going to his lowermost ribs his eye lights sharp as he watches Runix writhe in his hand. Runix lets out a rather loud moan as he cums, clenching around Sans' tongue panting heavily. Withdrawing his tongue, Sans presses his smallest phalange against Runix' entrance.

 

"You reedy, Rune?" Sans asks getting a shaky nod in reply before slowly slipping his phalange into Runix' tight hole.

 

"Nnnnnggg ahnnn" Runix moans at the stretch, shuddering and panting heavily in Sans' palm as Sans sets a slower pace trying not to overwhelm him. "F-faster Sans!" He begs, all but screaming another ragged moan as Sans does just that rapidly ramping him up for another orgasm. Panting heavily from oversensitivity, Runix lets out a soft whine as he cums again getting some on Sans' hand. Passing out almost immediately after, Runix curls against Sans' thumb.

 

Sans cleans Runix off in the sink as Runix sleeps on, laying his smaller mate against his chest and falling asleep on the couch. Neither wake when they return to their usual sizes, Runix still slightly smaller than Sans but not such a large difference in size anymore. The two mates sleep on, cuddled in each other's embrace.


	11. Day 11: Cross-Dressing

**Summary for the Chapter:**

> Reaper x Runix
> 
> This outfit is deadly

"You can come out now Runix, it doesn't take that long to change" Reaper teases an easy smile on his face as he sits on the couch in their shared bedroom waiting on Runix to come out of the closet. Heh, the closet. Runix walks out sheepishly looking down at the floor, wearing the long dress Reaper had picked out for him to wear. The material went down to his knees, dark sapphire with little silver sparkles in it resembling stars. The outfit is finished with black wedges sitting snugly on Runix' feet.

 

Reaper whistles his appreciation of the outfit patting his clothed lap for Runix to sit down. Normally he wouldn't let anyone touch him because of his...heh...deadly touch but for some reason, Runix had remained immune so Reaper could touch him as much as he wished. And touch he did. There wasn't many a waking moment Reaper wasn't enjoying the fact he had someone he could cuddle, kiss, do all the couple things everyone else did with no problems.

 

Reaper is clothed in his usual outfit, he looks best in that in his humble opinion. Chuckling as Runix sits down in his lap, Reaper spies the sapphire choker he had requested Runix wear as well almost blending into the neck of the actual dress if it weren't for the chocker being black that is. "Stars Runie you look amazing in this dress" Reaper whispers, bringing a blush to adorn Runix' face the skelekitsune rather sensitive to his praise. A fact Reaper had abused time and time again, in the bedroom and not.

 

"Th-thanks" Runix stutters, bringing a chuckle from the death god.

 

"Let's make a mess of it, shall we?" Reaper asks, running his hands under the end of the dress teasing his way up Runix' femurs. Runix shudders, leaning against Reaper leaving said skeleton perfect room to lick Runix' neck earning him another shuddery moan. Reaper kisses Runix deeply, working his pelvis to form his member and ass teasing the slit with the tip of his phalange.

 

Moaning muffled through their kiss, Runix shudders as Reaper lifts the dress from his ass pulling his robe enough for his own erection to spring free teasing Runix' entrance. Runix breaks the kiss to moan loudly as Reaper hilts himself fully in one thrust. Runix moans helplessly as Reaper sets a deep yet slow pace, unable to wrap his legs around Reaper as the death god had sat him in his lap sideways at Reapers mercy to how fast and hard he wanted.

 

Moans fall freely from Runix' mouth as Reaper takes the chance to lick Runix' neck while he relentlessly pounds into his mate hard. "Cum for me, Runie" Reaper commands, bringing Runix into his orgasm following with a soft grunt a few deep thrusts afterward. "Heh I told you I was going to make you make a mess of this dress and look, you've come all over the inside of it" Reaper teases as he pulls Runix into another kiss, having not pulled out yet.


	12. Day 12: Costumes

**Summary for the Chapter:**

> Sans X Runix
> 
> Classically, this is something fun
> 
> heheh

"Sans I'm not so sure about this." Runix sayshis mate, coming out of their shared bathroom wearing the top half of a horse costume. Sans chuckles his half of the horse costume already on.

 

"Just wanted to try something. Now c'mon I want to see if this fits right with the both of us." Sans ushers, seemingly in a hurry for the first time Runix had ever known him. Sighing, Runix complies. Laughing, Sans slides against Runix' summoned ass in the costume as it wouldn't fit without summoning it.

 

Runix jolts as he feels Sans' hands wrap around his waist palming his clothed member working it to 'attention'. Runix tries to muffle his moans as Sans continues to work his member up through his pants, humming quietly to himself. 

 

"So you ready for what I really wanted us to wear this for?" Sans' voice rings out in the darkness inside the costume. Runix nods, for sure Sans can't see him until he feels Sans lower his pants past his ass one hand teasing his entrance. Gasping out a moan past his hands, Runix almost buckles as Sans gets closer, spreading his ass and plunging his tongue inside his ass.

 

"S-sansssss" Runix moans as Sans continues his ministrations, bucking against empty air as Sans continues tonguing his ass. Neither of Sans' hands is on his member now, too involved in holding Runix' hips so he can't squirm away not that he'd want to at this point.

 

"Walk to the bed and bend over against it. I know it's tall enough." Sans commands as he removes his tongue from Runix' ass his voice deeper and more arousing than usual. Complying, Runix makes sure not to move too fast as to lose Sans attached to his hips or trip due to his pants at his feet. Bending over the bed, Runix is almost knocked onto the bed moaning loudly as Sans slides up to the front of the costume sliding into the hilt in one hard thrust.

 

Sans set an unusually fast pace, normally he sets a slow yet hard and deep pace but today Sans is all over him, hands and mouth reaching everywhere they can to leave Runix a moaning panting mess only being held up by the combination of Sans and the bed.

 

"S-so close!" Runix cries out as he feels Sans change the angle slightly making him see stars as it makes Sans hit something deep inside, the friction from the bed and the costume he's wearing on his member making him cum hard with a strangled moan. Sans utters a soft curse as he unloads inside Runix, panting heavily as he lays across Runix' back still buried deep inside him.

 

"S-sans...that...that was..." Runix stumbles with his words, moaning softly as Sans pulls out and helps him out of the costume, Runix falling onto the bed bonelessly as he can't feel his legs.

 

"Love ya Runie, thanks fur letting me try that" Sans purrs, kissing Runix gently as he uses his magyk to dump the costume in the wash sitting next to Runix offering him a chocolate bar which Runix greedily accepts.


	13. Day 13: Massage

**Summary for the Chapter:**

> Massage
> 
> Outer X Runix
> 
> Okay i feel the worst about this one

Runix and Outer get home exhausted, sore and tense in Runix' case as he had to keep running from Outer's Undyne as she kept wanting to challenge Runix to a spar to which Runix always said no. He was afraid of hurting the fish monster and killing her just like he did his own Undyne. Runix would never forgive himself if he caused anyone of Outers friends to die or get hurt because of him. "You ok Runie?" Outer asks as they enter the house. They were lucky Outer's bro had managed to distract her long enough for Runix and Outer to make their escape, making a quick shortcut to the house and rushing inside before they could be seen and stopped by anyone else.

 

"Stars above Runix you're so tense" Outer observes as they lay in bed together after a long day napping at Outers various stations. Despite Runix' offers and protests, Outer didn't want him to bring them all down to earth...especially how they finally found out what the humans had been up to since their sealing years ago. It had been almost completely a unanimous decision made by the monsters to wait until the humans could learn to control themselves better.

 

"Here, let me help" Outer suggests, rolling Runix onto his front straddling his pelvis from behind. Runix shivers lightly as Outer does so, feeling Outer place his hands on his shoulder blades. In a flash of magyk Runix is in his larger human form the multiple scars standing out even more on his pale skin than it did on his bones having more mass in this form.

 

"Good idea Runie, it's easier to massage actual tissue than just bone" Outer whispers before starting at Runix' neck gently massaging the tenseness out of the muscles surrounding it making sure to be careful not to accidentally choke Runix in the process. 

 

Moving to Runix' shoulders, Outer whistles as he hits a particularly stubborn knot between Runix' shoulder blades. Runix tries to relax the best he can, making small hissing noises as Outer works the knots in his now muscles and magyk leaving him a boneless pile on the bed as Outer works his way down to Runix' waist stopping there. Getting off Runix, Outer pulls him into his arms, smiling softly as Runix nuzzles against him enjoying the feeling of Runix' scars against his phalanges Runix shuddering as they are even more sensitive in his human form than the other ones.

 

"Hnnnn" Runix mumbles, burying his nose against Outers ribs, his magyk covering him once again returning to his normal form the skelekitsune. His soft fluffy tails wrap around Outer as he goes to sleep in Outers arms content at the world. The two could figure out what to do with the situation dealing with a spar later, they both didn't want to deal with it. Especially not now, while a good friend she was rather exhausting.


	14. Day 14: Somnophilia

**Summary for the Chapter:**

> Nightmare x Runix
> 
>  
> 
> google search: tent-
> 
> Tentacle hentai
> 
> heh

Nightmare walks into the room they all share, seeing Runix asleep curled into the center of the bed. Nightmares spot. Nightmare shrugs, getting undressed and into bed next to him exhausted from dealing with Ink and his brother that day. As if sensing his presence, Runix curls up against him purring in his sleep. Nightmare smirks, drifting off to sleep to the sound of his smallest mates purring.

 

Only to wake up an undetermined time later with a raging hard-on and an asleep Runix attached to his chest like some kind of adorable skeletal koala bear. Nightmare tries to use his tentacles to pry Runix from him so he can rub one out but is stopped by a soft moan from Runix in his sleep.

 

Raising a brow ridge, Nightmare realizes how naked Runix is having his own magyk summoned into his usual member and juicy plump ass. Deciding that while they had discussed something like this before it just hadn't actually happened before Nightmare decided to go with it.

 

Turning over so that Runix is pinned beneath him, Nightmare rests his smallest mates legs on his shoulders presenting Runix fully to him. Curious, Nightmare places a phalange against his entrance causing Runix to breathily moan out in his sleep.

 

"Nnng Night...mare" Runix moans out, causing the feared leader of the dark 'Sans' to blush a deep blue himself looking down once again at Runix' summoned genitals. Slowly, ever so slowly, Nightmare prepares Runix for his member savoring every small noise and erotic breaths that Runix lets out surprised the smaller is still asleep.

 

Grunting as quietly as he can while he slips his member inside Runix' ass, Nightmare stills listening to Runix' whimpers and whines before setting with a slow pace one of his tentacles pumping Runix' member in time with his slow thrusts. Glancing up from his work on Runix, he's greeted with hazy sapphire eye lights already one step from becoming hearts.

 

"Nnng...Nightmare. P-please...h-harder" Runix slurrs, still partially asleep as he moans out his request his words stuttering and stopping in places. Nightmare smirks before speeding up, thrusting hard in Runix watching in sheer pleasure at the power over him as Runix goes from half asleep to fully awake and moaning loudly. No doubt the others could hear them now with how loud Runix is getting with his gasps, his pleads and his moans for Nightmare. Only Nightmare himself could reduce such a being to a debauched state and the sight of such sends arousal shooting straight down his spine.

 

Growling lowly in his throat, Nightmare bites down hard on Runix' neck marking him with a small black pentacle that pulses with his magyk. Satisfied with his work, Nightmare makes quick work to reduce Runix into a puddle of pleasured skeleton bringing orgasm after orgasm from Runix. His thrusts stutter as he cums hard in Runix causing Runix to cum again. Pulling out slowly, Nightmare uses his tentacles to clean Runix up who cuddles to him again. Groaning in fake exasperation, Nightmare allows it and holds his smallest close to him feeling the others join their cuddle pile as he falls asleep his tentacles wrapped around his gang.


	15. Day 15: Uniform

**Summary for the Chapter:**

> Error x Runix
> 
> Guess who was maid to dress up?
> 
> I'll give you a hint: It isn't the dominant in this one, that's fur sure

"E-error, do I have to wear this?" Runix stutters from behind the door peeking around the doorway only part of his head showing.

 

"YeSs," Error smirks, watching as Runix steps out in a skimpy maids outfit "YyyoU lLost the BbetT aFteR aLl" Error chuckles, watching as Runix tries to smooth out the skirt that doesn't fully cover his pelvis.

 

"Y-yeah" Runix mumbles "Stupid bet"

 

Error laughs at Runix' prediciment, hiding his erection with his arms as he leans foward. "NnoW Ggo cLeeAn S-SsoMeThInG" Error commands throwing Runix a duster. Catching the duster with his magyk, Runix proceeds to start dusting the entertainment center having to bend down to get the lower half of it. By the time Runix is finished with the tv, Error can't stand it anymore. The sight of those scarred bones like the only work of art he ever enjoyed had his member throbbing to be within Runix' tight ass.

 

Snatching Runix up and taking him to the bedroom, Error shoves him onto the bed. "BbenND OvEr tThE E-eDgE." Error commands to which Runix redily obeys, eagerly presenting his pelvis to Error his magyk forming into his plump ass and member shivering in anticipation. Error didn't usually want to take command like this, usually patiently working Runix into a pleading begging mess before getting down to it but when he did it always left Runix weak in the legs and wanting.

 

Error palms his erection freeing it from his shorts the dark blue to black gradient member springing out as he pulls them down just enough to let it out. Taking his hands he spreads Runix' ass watching as Runix shivers in anticipation slowly sinking into Runix' tight heat growling deeply at the feeling of being buried in him. Runix had been his first before any of the others after all. It was Error who first tasted all the skelekistune had to offer before showing him to the others. Now the lonely kitsune had many to call mate but Error would always have a special place in addition.

 

Only for Error Runix would let his guard down this much, let his expressions free like this. None of the others would be able to make Runix want their attention so much as the one who saved him from his lonliness, as he saved them. Error grunts, thrusting foward drawing sweet moans from Runix as he writhes beneath him. Wanting. Willing and pliant for anything Error gives him.

 

Leaning down, Error bites the other side of Runix' neck deepening his own mating mark that he had made shortly before Runix joined the group as their smallest mate and the gangs' healer. All it had taken from Error to convince Runix to do so was for Error to ask him and he was there.

 

"ahhnn E-error" Runix moans out, clenching around Errors member as he cums hard, Error cursing lowly as Runix' ass clenches around him bringing him to cum within Runix after a few stuttered thrusts. Pulling out slowly, Error helps Runix to lie down the two curling against one another as Runix drifts off to sleep Error watching on reading a book as he gazes at his sleeping mate.


	16. Day 16: Sixty-Nine

**Summary for the Chapter:**

> Sans x Runix
> 
> Sixty-nine is a classic position, right?
> 
> Why not with Classic Sans?

"S-sans?" Runix calls as he's pinned to the bed with blue magyk looking around for his mate unable to find him immediately. "Sans wh-" Runix calls only to be silenced by Sans' mouth on his own silencing him mid-sentence. Sans' eye lights regard him sharply sending arousal straight down his spine. He had been getting some 'alone' time since Sans' work schedule for once was too busy for them both to share some intimate times but had been frozen with blue magyk moments before his release.

 

"So naughty, playing with yourself without good ol me around to at least enjoy the show" Sans tuts, shaking his phalange in a warning sort of fashion in front of Runix as he straddles Runix' waist. "Such a pity I was planning something special for the two of us. I guess i'll have to wait till some other thyme" Sans teases, going to move only to be stopped by a whimper by Runix his body shivering despite the binds of Sans' blue magyk.

 

"Oh so you want some, don't you? Well, I soup-ose I can spoil you just this once" Sans concedes, not letting Runix he was going to concede anyway. Ridding himself of his own clothes, Runix finds himself face to face with Sans' own member a few shades different than his own sapphire shaft. "Work for it then" Sans commands, tugging on Runix' member languidly, as if waiting for something.

 

Runix gets the message loud and clear. Licking a solid stripe up Sans' member, he grasps Sans by his waist taking his member fully using his tongue to the best of his ability to work Sans into a moaning mess. Sans' knees buckle as Runix swallows around him cursing lightly. Two could play at this game. Taking Runix' member in his hand, Sans slowly takes his mate into his mouth working Runix' member in a way that always drove Runix up the wall with pleasure smirking the best he can when he hears Runix' muffled moans around his own member.

 

Soon the room is filled with the sounds of muffled moans as one tries to out-do the other, Sans teasing Runix' ass with one of his hands slowly fingering his mate as Runix writhes sucking down Sans' member like he was starving. A soft cry is all the warning Sans gets before Runix cums in his mouth his ass clenching around Sans' phalanges. Thrusting a few more times Sans cums in Runix' with a soft curse pulling out and moving to face Runix. Runix cleans both their faces off of cum as they lay in each other's embrace enjoying the rest of the day lazing around.


	17. Day 17: Collaring

**Summary for the Chapter:**

> Red x Runix
> 
> Fits, doesn't it?

"I...I got somethin fer ya darlin" Reds familiar drawl rings from the hallway as he enters the living room where Runix was watching a movie. Pausing the movie, Runix turns to Red gazing at him with his sapphire colored eye lights.

 

"Yeah Red? What is it?" Runix asks, as curious as a fox ever could be, looking to where Red is holding a small box in his hands his eye lights catch Red fiddling with the box as if he's unsure if Runix would like it or fearful of his reaction to whatever is in the box.

 

"Well...ya remember how much importance collars have in Underfell before we left the underground right?" Red asks, gaining a nod from Runix who still looks confused about what that particular fact has to do with anything right now as they are on the surface. There was a rocky start but the humans were amiable to the fell verse monsters, especially after their swap and tale counterparts vouched for them.

 

"Yeah, what about it?" Runix asks, watching as Red approaches with the box slowly opening it. Inside the box is a purple color the same shade of their magyk when the two colors mix, silver studs adorning the soft leather even softer plush on the inside of the collar for a snug soft fit.

 

"Oh stars Red it looks amazing! Is this for me?" Runix asks his eye lights turned into little hearts as he gazes from a flustered Red to the collar inside the box. Red nods, mumbling about how it's made from his magyk as he watches Runix' excited reaction to Red giving him a collar.

 

"Yer...yer knot disgusted with it?" Red asks, unsure.

 

"Of course knot silly!" Runix teases, "May I put it on?" Runix asks gently taking the collar out of the box when he gets a shaky nod from Red. Sliding the collar on, Runix clasps it shut so that it sits right over the scar going straight across his neck. "How do I look?" Runix asks Red, turning his head so as to kind of show off the new collar.

 

"Yer look amazin darlin" Red says softly, gazing amorously at Runix, love, and compassion in his gaze as his eye lights turn into little hearts too. "Stars above Runie I'd love to see what yer look like all spread out fur me in that collar." Red gushes, sitting on the couch and pulling Runix into his lap to pull him into a burning kiss.

 

"Well, why don't you? We have the house to ourselves for now." Runix answeres, finding himself ported to the bedroom faster than he can get half the sentence out, moaning as Red attacks his neck where the collar isnt covering as it's a tad bit thin but just the perfect size for Runix' lithe neck.

 

"I can't wait to wreak you, have you writhing under me begging for more as I hold you up by this here collar, to have it glistening against yer bones covered in yer sweat as I pound you into the mattress" Red growls, his claws roaming Runix' form. Runix gasps and keens as Reds claws tease sensitive scars located all over his body, his eye lights becoming hazy with arousal.

 

"Why don't you then?" Runix challenges breathlessly, kissing Red hard as Red makes short work of their clothes, throwing them in a pile by the side of the bed.


	18. Day 18: Fucking Machine

**Summary for the Chapter:**

> Error x Runix
> 
> Someone gets a little 'strung' up eh?
> 
> Bonus: a little bit of suspension. Just a bit.

"Y-yoU rReaDdY?" Error asks Runix as he tests the tightness of his strings, Runix being strung into a position hovering above a machine with a toy sticking midway across the seat of said machine. A long cord protrudes from one end leading to a device in Errors hands. 

 

"Y-yeah" Runix stutters, remembering having suggested possibly finding something for when Error wanted to 'mess around' with one of the gang but couldn't touch them for...reasons he'd rather not think about. None of them would ever want to force the glitchy skeleton to do something he didn't want. Or any of the group for that matter.

 

"SsAff-eE w-WorD?" Error asks, tilting his head as he watches for any sort of negative reaction. Runix glancing down at him from his position hovering over the said machine taking pride that he is the first of the gang to see Runix use one of these. 

 

"X-xio" Runix stutters, shivering in anticipation. The two had never played like this and Runix hesitated to admit how aroused he is without them even starting yet. Nodding, Error slowly lowers the skelekitsune onto the machine watching intently as Runix moans softly as the toy breaches his ass. Runix squirms as he's fully seated, Errors strings still holding him up, at this point to make sure he doesn't fall off. The whole gang always worried about Runix hurting himself no matter what kind of situation they were in, intentional or not.

 

Setting the machine to low, Error watches sitting down in a recliner facing the bed as Runix moans in ecstasy his eye lights hazing at the edges starting to round out into hearts already. Smirking, Error turns the machine up a notch palming his own erection as Runix' moans increase in pitch and volume.

 

"ahhhh nnn E-error!" Runix moans out as said glitchy skeleton turns up the intensity again, the toy inside relentlessly pounding into him. Error smirks as he watches Runix' eye lights change into hearts the closer his pet got to cumming. Runix arches against his bonds as he cums hard screaming out Errors name panting heavily. Lowering the machine to its middle setting Error keeps it going through Runix' orgasm. He only stops once Runix' shuddering gets too heavy, his nonverbal tell when he's had enough.

 

Helping Runix off the machine in a gentle way few outside their group had seen Error ever treat anything, he sets the machine aside to clean later. That could wait. Once laid on the bed, Runix' eye lights take a few minutes to steady, his conscious thoughts following shortly after.

 

"E-error?" Runix calls, looking around before his eye lights focus on Error standing at the edge of the bed to his right. "Y-you didn't get to-"

 

"i'M fFiNe, RruNnE" Error cuts him off with a raise of his hand passing Runix his favorite snack, a bottle of ketchup. Grasping the bottle in shaking hands Runix guzzles the whole bottle. A snap of phalanges and all the soiled sheets are removed, ported into the laundry room waiting to be washed, watching as Runix drifts to sleep with the blanket Error had knit him his birthday. "HheH. LliTtlE ssSsHitT" he mumbles as he watches Runix sleep after he had cleaned and put away the 'toy'.

**Notes for the Chapter:**

> if you've gotten this far yeeee!!!
> 
> also, i'm kinda leaving day 31 to a sort of vote. A combination of at least two of these kinks so far with whatever pairing you'd wish with Runix. I'll try and tally and do the one that wins....as long as i'm actually able to actually write it.


	19. Day 19: Public

**Summary for the Chapter:**

> Blue x Runix
> 
> something something don't get caught zoneee tehe

"B-blue c-calmn down we're outside damnitt!" Runix whisper-yells to Blue who is currently leaning heavily on Runix his hand sneakily teasing the base of said skelekitsune's tails which are extremely sensitive. The two were leaving a party in which Blue had insisted was a costume party, Blue going as a knight and Runix going as an assassin. The 'skin' tight outfit meant, unfortunately for Runix' increasing embarrassment, that Blue's hands roamed his form all night especially with his ecto body formed underneath the costume the whole night.

 

Which left them as they are, wandering through the dimly lit areas of Waterfall trying not to be seen with Blues hands all over everywhere they could reach. Blue carefully guides Runix to the cave behind the waterfall that Alphys had made for whatever reason, his arousal throbbing behind his armored plates at the thought of being caught in the act. That and to Blue, Runix looked rather delectable in his assassin outfit the tight-fitting garment cupping his mates ecto flesh in just the right ways.

 

"Mwehehe do you know how hard it was not to bend you over the couch right there in front of everyone and have my way with you?" Blue whispers into Runix' ear as he lets go of Runix' tails. "It was excruciatingly hard" Blue continues, grabbing onto Runix' hips and grinding his hardened erection against Runix' deliciously plump ass to punctuate his words.

 

"B-blue!" Runix cries out, moaning softly as Blue makes quick work of his pants lowering them enough for his plump ass to peek out. His legs shake as Blue teases his ass spreading and squeezing, Blues phalanges teasing his entrance but never entering.

 

"Get on your hands and knees on that bench over there" Blue commands, scratching lightly on one of Runix' ass cheeks earning him a startled moan. "Now" Blue punctuates with a light smack to the other, Runix quickly making his way to the bench doing exactly what Blue said blushing deeply as his magyk color. Blue approaches slowly, circling Runix on the small bench seemingly appreciating the view of his mate on hand and knee in such a risque place.

 

"Such a good mate you are. Let me reward you" Blue purrs, squeezing Runix' ass before sliding in all the way in one firm thrust earning him a drawn-out moan from Runix. "Do you like this, oh dear Runix? The high risk of being caught by someone walking by and hearing the lewd noises we're making right now?" Blue teases as he immediately sets a brutally fast pace almost throwing Runix onto his face, able to catch himself on his elbows.

 

"O-oh fffuck, oh st-stars B-blue!" Runix cries out as Blue continues, enjoying every pleasured noise coming from Runix. Blue moans deeply as his mates' ass clenches his member hard, sapphire colored cum coating the surface of the bench as Runix cums. "Such a naughty boy, getting cum on the bench" Blue grunts as he slows making hard thrusts as he cums deep, riding them both through their orgasm before pulling out marveling at the sight of his lighter blue colored cum dribbling out of Runix' darker blue ass. Blue carries the blushing Runix home, not bothering to clean them up as he makes love to him throughout the night, his stamina not quenched just yet.


	20. Day 20: Skull-Fucking

**Summary for the Chapter:**

> Horror x Runix
> 
> Because hole-y fuck

"A-are you s-sure H-horror?" Runix asks, looking unsure with himself, twiddling his phalanges as he regards his larger mate kneeling on the floor in front of him. To say Runix wasn't at least a little hesitant when Horror approached him and asked Runix to skull fuck him was the understatement of the year. Especially since Runix is one of the smallest of their group and Horror is one of the larger ones.

 

"Very" Horror rumbles, his single eye light boring into Runix intensely. "I want you," Horror whispers, raising to eye level with Runix "To fuck my skull with yer cute lil erection." Horror finishes, his hot breath rasping against Runix' neck as the larger drinks in the sight of Runix. Runix, while admittedly aroused, deeply ashamed of being aroused by such a thing. He didn't want to hurt Horror and very much feared to do so.

 

"Ya won't harm me more 'n I want." Horror grumbles, kissing Runix "I know the safe word."

 

"Y-ya promise? W-what is the safe word then?" Runix asks, shakily standing his ground wanting to make sure the terms were set.

 

"Yes, 'n ill tell ya if yer go too far. I promise." Horror whispers his deep baritone sending shivers up Runix' spine as it lowers even more.

 

"O-ok. I-I'll do it." Runix says with determination, watching as Horror nods getting up and laying across the bed his head hanging off the edge giving Runix a good angle at which to use the gaping hole in Horrors skull while being able to watch his expression for any dishonesty or discomfort. Runix slowly reaches a few phalanges into the gaping hole in Horrors skull, getting the feel for the magyk inside pressing against them.

 

"Thas...thas good...hhhhh" Horror moans deeply, almost sounding like a growling purr his single eye light slowly turning into a large heart shape. "C'mon...you cn do more" Horror persists, a red blush coloring his scarred skull. Runix nods numbly, removing his phalanges and placing his member at the hole. Taking an unneeded breath he braces Horrors skull in his hands slowly sliding his member in spurned on by Horrors guttural moans and gasps for more.

 

Runix slowly increases his speed being careful not to thrust too hard not wanting to make the hole even bigger, Horrors moans making it hard to do so. "H-horror i'm gonna-" Runix tries to warn.

 

"D-hhhhhh-do it!" Horrror all but demands moaning heavily as Runix cums within his skull, cumming himself despite how ignored his own erection was. Runix pants heavily, pulling out of Horror earning him a soft groan of approval. "Y-yer did great Runie" Horror praises, moving to sit up his single eye light wavering as Runix' cum moves around in his skull. Runix goes to help him clean the cum out of his skull but is stopped as Horror holds up a hand. "Leave it. It'll dissipate after a while. Fer now...I want it to stay." Runix nods settling with cuddling with Horror in the large armchair in the living room.


	21. Day 21: Blood Drinking/ Vampirism

**Summary for the Chapter:**

> Red x Runix
> 
> Gues who's the vampire this thyme?
> 
> tehe

"Red? Red you ok? Fell said you've been locked down here for days, I'm sorry for being busy with...well, you know." Runix whispers as he enters the darkened basement of Fell's house. Red had left to visit his brother and hadn't returned in a few days, which was normal for Red but Fell had called mentioning that after the first night when Red had gone walking around midnight he had locked himself in the basement and wouldn't come out for anything even the promise of mustard.

 

"You shouldn't bee in here" Red's voice rang through the dark room, bouncing off the walls making it hard to locate him on sound alone. "Stars I've missed you so, but it's too dangerous to be around me now." Reds voice rings again.

 

"Dangerous? Really Red? C'mon I'm an lv 16 being that can't apparently die for fuck's sake! Stars above knows I've tried" Runix calls exasperatedly. "So come here and turn some kind of light on I promise nothing you're gonna tell me is going to make me want to leave" Runix promises, meaning every word feeling the determination in his 'soul' pulse with his conviction.

 

Suddenly, a lamp is turned on in the corner, Red standing right in front of him his clothes rumpled and ripped a very clear bite mark on his neck the bone around the mark purpled with an apparent bruise. "Told ya that ya woodn't like what ya sea," Red says after a pause to be shocked as Runix rushes to him and hugs him.

 

"You fucking bastard you had me and everyone else worried sick!" Runix scolds, tears falling from his eye sockets as he practically hangs off of Red.

 

"But can't ya see, I'm a fuckin vampire now! I got ter live off of blood-" Red protests to be cut off as his face is shoved against Runix' neck, Red almost losing it and giving in to the temptation to drink Runix' delectable smelling blood right then and there.

 

"You can always drink from me, Red. There is no risk of you killing me by accident, even if you do manage to drain me dry." Runix whispers, pressing Reds mouth against his presented neck, shivering as his fangs press lightly against the bone there. Red's resistance shatters as he buries his fangs into Runix' willing neck with a muffled moan at the taste.

 

"A-ahhh R-red d-drink u-up" Runix moans, reaching down to palm his member when Red beats him to the punch grinding their clothed erections together as he drank deeply from Runix. It doesn't take long for Runix to cum, the stimulation from Red drinking his blood and grinding hard against him pushing him over the edge Red not far behind him.

 

Runix passes out in Reds hold as Red removes his fangs from Runix' neck, licking the wound closed as he's sated for now. Fixing his clothes, Red carries the sleeping kitsune out of the closet, explaining the situation to his brother in hushed whispers before porting home tucking Runix in and watching his slow breathing as he sleeps.


	22. Day 22: Threesome (or more)

**Summary for the Chapter:**

> Killer x Cross x Runix
> 
>  
> 
> a 'sanswich' huh?

"C-cross? K-killer?" Runix stammers, waking up from healing the two to them kissing him everywhere. 

 

"You healed us so well. Let's show you our appreciation" They say simultaneously, making embarrassingly quick work of Runix' clothes and their own placing kisses everywhere they can reach. Runix moans softly as one of their phalanges brushes against the scar spanning his whole rib cage. 

 

Soon Runix found himself lying between two of his mates gasping and writhing in pleasure as they each took a side touched, caressed every part of him. Runix' magyk forms with a soft pop, causing both Killer and Cross to pause long enough for it to form before pleasuring their slightly smaller mate doing their best to turn Runix into a boneless pile on the bed.

 

"You look so gorgeous spread out between us like this" Killer whispers against Runix' left side, Cross nodding. "Cross lay down. Our little lover is going to ride you." Killer commands, watching as Cross gets comfortable on his back waiting. Killer helps Runix straddle Cross hovering over Cross' hardened member shivering in anticipation.

 

"mmmmffff" Runix moans as Killer presses his tongue into Runix' ass at the same moment Cross pulls him down for a deep kiss pressing his tongue inside Runix' open mouth. Tears of pleasure trickle down Runix' cheeks as Killer thrusts his tongue deep within his ass, muffled moans of their names escaping. When Killer deems Runix ready he removes his tongue slowly lowering Runix onto Cross' member enjoying the sound of his two mates moaning in tandem as Cross hilts inside Runix.

 

Cross' hands grasp Runix' hips thrusting up as he pulls Runix down, Runix' gasping moans music to their 'ears' as Runix begs for more. Killer smirks as he pulls the two of them to the edge of the bed drawing a strangled moan from Runix as he licks and nips at Runix' neck, helping Cross bounce Runix on his lap. With a soft cry, Runix cums getting some on all of them Cross following shortly behind with a muffled curse.

 

"My turn, Rune" Killer whispers into Runix' ear said skelekitsune shuddering, still very aware of Cross inside of him. Helping Cross to stand while still inside Runix causing Runix to wrap his legs and arms around Cross to avoid falling, Killer wraps his arms around the both of them giving Cross a look. Cross grunts, lifting Runix off of his member Runix whimpering softly as Killer slides right in. Cross' member brushes against Runix' as he finds himself pressed between the two of them.

 

Killer sets his own brutal pace causing both Runix and Cross to moan loudly into each other's mouths as the movement causes their members to press and rub against each other. Runix' moans escalate as Killers member reaches deep, hard thrusts having him seeing stars after Cross left him breathless from earlier. It doesn't take long for Runix to cum again, being oversensitive from earlier, Cross following with a muffled curse. Killer swears as he cums deep in Runix hips stuttering as he pulls out and the two places Runix between them cuddling their smaller mate in his sleep sanswiched between them.


	23. Day 23: Size Difference

**Summary for the Chapter:**

> Horror x Runix
> 
> why not one of the largest?
> 
> let's make him larger

"S-sorry Horror" Runix stammers as he tries to clean the potion off of Horror. Horror grows another foot in size, his single eye light bearing down on Runix intensely. "H-here let me get the antidote ready i-"

 

"Don't just yet..." Horror interrupts, gazing at Runix with a rather intense stare. Runix looks up at Horror to be scooped up into his lap on the couch and kissed deeply, Runix practically melting into the kiss arching against Horror and moaning softly.

 

"H-horror w-wha" Runix pants, cutting himself off by a rather loud moan as Horror makes startlingly quick work of Runix' clothes and licks a stripe along the scar across Runix' sternum. "Hnnahhhggg H-horrror..." Runix pants out, his magyk having already summoned feeling the much larger than usual bulge in Horrors shorts. Runix feels an odd mix of fear for how large it is and arousal in the thought of Horror spreading his ass wide with his erection.

 

Horror seemingly knows what Runix wants before he even says it, pulling Runix into a kiss as he slips a phalange into Runix' tight ass. He ever so gently stretches Runix preparing his even smaller seeming than usual mate for his larger member not wanting to harm him. Runix pants and whines in his lap, wiggling wanting Horrors girth inside stretching him wide.

 

Spurned by Runix' pleading moans and whines, Horror withdraws his phalanges with a grunt. Lowering his shorts just enough to let his engorged member out, Horror lowers Runix onto his member as slowly as he can swallowing Runix' moans and whimpers with a kiss. "So tight Runie. Not gonna last long like this with yer ass squeezin me so tightly" Horror admits, punctuating his words with a hard thrust.

 

Grasping Runix by his hips, Horror pistons Runix onto his engorged member filling the room with the sounds of Runix' moans and the slapping of ecto flesh against ecto flesh. With each thrust Horror can see Runix' stomach bulge with his member filling him with a strong sense of want, pounding into Runix harder.

 

"Ahhh hah H-horror! C-close!" Runix manages to moan out past Horrors brutal pase leaving him seeing stars breathlessly moaning his eye lights rolling to the back of his skull threatening to pass out from the pleasure of being fucked so thorougly. Horror growls, increasing his tempo as he feels himself getting close too. The whole group, himself included, like to cum right after Runix wanting to make sure their smallest is pleasured as tehy all enjoy the looks he makes when he's lost in pleasure.

 

Runix comes with a sharp cry, coating his crotch in his cum and clenching even harder around Horrors girth. Horror comes with a growl, biting down hard on Runix' neck as he does so prompting Runix to cum again passing out in his arms as the intensity of two orgasms right after another is too much for the smaller mate. Pulling out gently, Horror takes Runix to the bathroom cleaning him up and dressing him in pajamas, holding Runix in his lap while Runix sleeps.


	24. Day 24: Shower/Bath

**Summary for the Chapter:**

> Reaper x Runix
> 
> c'mon, it's Reaper bruh
> 
> Why knot let them get dirty and clean?

"Decided to take a shower without me huh?" Reaper teases as he floats into the bathroom where Runix is currently relaxing in the tub, eye sockets opening upon the death gods entrance into the room. "Mind if I join you?" Reaper asks to get leveled with a 'What the hell are you on of course you can' from Runix, chuckling as he slips his robe off to float into the tub with Runix.

 

"Reaper you goofball" Runix chuckles, sinking further into the water. He had originally made a bubble bath in their large tub to rub one out in comfort before Reaper came home but Reaper walked in the door just as he was getting started leaving Runix with a hard-on in the tub with his mate.

 

"Don't think I don't notice what you are trying to hide under the bubbles, Runie" Reaper teases, his foot carressing Runix' 'hidden' erection causing Runix to groan softly. "I'm knot that slow you know." Reaper whispers, sitting in the center of the tub the water up to his neck motioning for Runix to join him.

 

Runix makes his way to the center of the large tub, his soft yelp turning into a moan as Reaper grabs Runix and pulls him to straddle the death god, their members brushing against one another in the warm water. Reaper immediately sets to teasing Runix' ass, drawing out small moans as Runix leans his head against Reapers shoulder.

 

"Were you waiting on me to find you so I could make a mess of you in the tub?" Reaper teases as he slides the third phalange in, Runix keening softly against the side of Reapers skull. Spreading Runix' ass wide as he removes his phalanges, Reaper lowers Runix onto his member. The water sloshes around with their movements splashing onto the marble floor.

 

"R-reaper" Runix pants, the warm water feeling warmer as the death god slowly makes love to Runix, ignoring how Runix begs for faster and harder wanting to savor every small sound Runix makes as he takes his time turning his mate into a wreak. "P-please" Runix tries to plead only for Reaper to silence him with a kiss.

 

Reaper continues his slow and steady pace, hitting deep every thrust Runix writhing on his member the water splashing with every movement. "Oh so you're too lazy to-" Runix cuts off as Reaper lifts him almost completely off of his member slamming Runix down hard. Runix gasps, his moan lost as a intense jolt of pleasure shoots up his spine causing him to cum hard clenching around Reaper.

 

Reaper curses as he cums a few slow deep thrusts later, watching as Runix' stomach fills with his magyk the two shades of blue looking almost black inside Runix' sapphire colored magyk. "You brat" Reaper jokes, kissing Runix gently as he helps the other clean himself off snapping his phalanges to clean the bathroom as he carries Runix to help him dress.


	25. Day 25: Bukkake

**Summary for the Chapter:**

> Runix asks for a rather...lewd thing from his datemates
> 
>  
> 
> One they are rather happy to indulge him in

"H-hey Nightmare?" Runix asks standing in the doorway to Nightmare's office, looking at the ground shyly a large blush permeating his skull making him look quite adorable.

 

"What is it Runix?" Nightmare asks as he looks up from his paperwork. He had been trying to see which au's would be feasible to live in if this house ever got attacked so they could have somewhere to flee to just in case.

 

"Can...can you all, um" Runix pauses trying to find his words. "cum on me at the same time?" Runix stutters out not seeing how Nightmare had dropped the papers in shock. Runix looks up to see Nightmare give a rather hasty nod, quickly calling the others into the room to tell them what their newest wished, the others having a similar reaction to Error with a few differences.

 

A few minutes later Runix finds himself fully naked in the living room on top of a clean sheet for easier clean up later. "Oh Runix, we're going to have fun covering you in our cum." Killer teases, cupping Runix' chin in his hands and kissing him deeply before joining the others in a circle around their newest and smallest mate. Runix is sitting in the center of his six mates, naked and willing. They were surprised when their smallest had gone to Nightmare and requested this but found the thought of him covered in their various colors of cum arousing so they all readily agreed.

 

Runix nods watching their looks of pleasure as they start pumping their members, resisting the urge to touch himself as it doesn't feel as nice when he does it. He doesn't want to ruin the moment by pleasuring himself in the midst of this so he can watch them as they cum. Cross is the first to cum, getting purple cum on Runix' left side his particular shade of purple looking like a good contrast to Runix' pale scarred bones. Dust and Killer are next with a soft curse getting Runix' back with Dusts being a lighter shade of purple than cross and Killer being an almost black shade of blue. Horror finishes on Runix next, his bright red cum standing out on Runix' right side.

 

Runix made sure for Error and Nightmare to be in front of him seeing as the two of them are the main leaders of the group and he wanted theirs on his front. It was nothing against his other mates he just wanted it that way. They must have already known that due to them arranging themselves this way without Runix saying anything.

 

Error and Nightmare finish at the same time with muffled curses, coating Runix' front in two different shades of bright blue, Nightmares having more of a purple tint to it but still blue while Errors had more of a neon tint to it despite being almost a navy blue. Runix' eye lights turned into hearts as he watches them cum all over him somehow enjoying being covered in his mates' cum as if they're marking him with their magyk.


	26. Day 26: Roleplay

**Summary for the Chapter:**

> With Error
> 
> of course
> 
> tehe i hope this one is decent

"YyOuV'E b-BeEn A bAddD ssStUddEnT, RruNE" Error scolds, pointing to a 'test' with a red F drawn on it and circled. He tuts in disapproval, waving the failing test grade and pointing to a pile of other papers.

 

"Is there anything I can do to make it up to you? Any way at all that I can...raise my grade?" Runix asks, lowering his voice and pointedly looking at Errors crotch.

 

Error seems contemplative for a moment glancing between Runix and the pile of papers. It's true they were all F's but almost 70's. "FfiNe. I-i'Ll gGiVe yYou ssOmE exXtRa c-CreDiT" Error conceedes, and Runix brightens at his change of mind "BbuT yYoU hhHaVe tTo wWoRK fForR iTttT" Error finishes with a motion to his crotch where his glowing member is tenting his shorts.

 

"Y-yes of course, thank you." Runix stammers, quickly going to his knees and crawling to Error palming the erection earning him a warning glare to get started along with a stifled groan. Reaching up and lowering Errors shorts enough that his member springs out. Hearing footsteps approaching, Error ushers Runix under the desk they are using with a quiet 'keep going' as Error slides closer pretending to do paperwork.

 

Runix takes Errors blue to black gradient member into his mouth, sucking lightly trying to hold back an audible chocking sound as Error presses him further onto his member. Runix can feel Errors hands shaking as he swallows hard around his member tasting pre release as he does so. Error cums with a muffled curse, a bitter sweet taste unique to the destroyer filling Runix' mouth as he manages to swalow most of it.

 

"GgeTt iN mMy lLaP" Error commands, pulling Runix' pants down as he stands up settling himself in the destroyers lap. Lifting himself up, Runix lines Errors member up groaning softly as his member slides into his ass. The stretch from Errors member spurning him on more as he slowly rides Errors member listening to Errors strained breathing.

 

"Hhhhh E-error" Runix moans as he's shoved onto the desk as Error stands up, slamming home in one thrust.

 

"DdiRty LliTtLe SslUt" Error groans as he pounds deep into Runix abandoning all sense of trying to be silent as he slams into his smaller mate. Runix' moans fill the room with the sound of their fucking, both monsters close to their orgasms. Runix comes first as Error curses, Runix' ass clenching hard around him as he roughly fucks him. Cumming hard within Runix, Error leans against Runix whispering in his ears about what a good slut he is as he fucks Runix to another orgasm.

 

Pulling out, Error watches as his cum leaks out of Runix' ass patting the abused ass before sliding their clothes back on watching as Runix stumbles off before following to make sure the smaller doesn't fall or something on those shaky legs.


	27. Day 27: Against a Wall/ On Furniture

**Summary for the Chapter:**

> Horror x Runix
> 
> against a wall? check
> 
> on some furniture? Check? do a washing machine and dryer count?

"ahnnnn H-horror mmmmmpphhh!" Runix moans as Horror kisses him fervently, pressing the smaller against the wall Runix' legs and arms wrapped around him. The two make out against the wall grinding against each other swallowing Runix' moans and Horrors growls. Runix' breathy moans make Horror's member twitch with arousal as he imagines the smaller laid on some kind of furniture as he wreaked him completely. Getting an idea, Horror prepares to change their location moving his hands to be able to carry Runix easily elsewhere. He had an idea.

 

"I'm going to wreak you" Horror growls, taking Runix' mouth in his own grinding against Runix' ass with his erection. Runix melts into the kiss even more at Horrors words pressing himself the best he can against the larger skeleton. The others were gone for a while and Horror was feeling a bit horny so why not? They could be as loud or as rough as they want and no Error or Nightmare being paranoid about Runix getting hurt. Taking Runix into his arms, Horror quickly rids Runix of his pants knowing Runix never bothered with underwear anyway sliding his member out of his shorts but keeping his on as he grinds their members together reveling at the lewd sounds Runix makes.

 

Carrying his smaller mate to the washer/dryer room, Horror sets Runix on the counter pumping their members together watching as Runix' eye lights turn to hearts. "H-horror" Runix moans, gazing at him lustfully. Growling deeply, Horror pulls Runix closer laying Runix across the washer and dryer after placing a pillow to support his head thrusting to the hilt in one go. Runix moans loudly as Horror sets a brutally fast pace his moans raising in pitch as Horror starts the washing machine and dryer the vibrations doing wonders for making Runix a sobbing moaning mess.

 

"Hah H-horror!" Runix moans as he cums hard, Horror struggling not to cum yet pounding deep into his smaller mate. "Ffff s-so h-hard!" Runix moans gripping the edges of the washing machine where his head is, crying from the pleasure as Horror continues to ravage him his eye lights fluttering towards the back of his eye sockets.

 

Runix cums hard, vision flashing white as Horror growls thrusting hard a few times before cumming almost exactly at the same time managing not to pass out just yet. Pulling his smaller mate into his arms, Horror pulls out gazing at Runix' blitzed out look, his eye lights completely hazy almost taking up his whole eye sockets. "Heh, yer took me so well Runie" Horror comments, to which Runix makes a small humming noise to. Cleaning them up, Horror sits on the couch watching tv while Runix cuddles in his lap his head resting on Horrors shoulder. Horror chuckles as he looks down and realizes Runix has dozed off just as the rest of the gang returns home, Nightmare seeing them shaking his head as he makes his way into the kitchen to see what is available for them to eat.


	28. Day 28: Glory Hole

**Summary for the Chapter:**

> Runix' mates find him in a rather 'fun' prediciment
> 
> this ones gonna be a bit longer than 500 words
> 
> sorry not sorry

**Notes for the Chapter:**

> don't forget about day 31. I have nothing planned and need ideas for which kinks would be good combined and who you'd like paired with Runix for it

"Um, guys? A little help? I'm kinda stuck in the wall." Runix calls from their shared bedroom. He was porting to the bedroom to get something but somehow got stuck in part of the wall within the bedroom right in the middle of the room where above his head their large tv hung on the wall. The others entered quickly, shock flickering across their skulls before something else showed. Lust.

 

Runix gulps as he feels his mates circling him, touching all over making sure he wasn't hurt. "So who's first?" Nightmare asks, looking at the gathered skeletons. Dust and Killer raise their hands at the same time glaring at each other before Killer holds his hands up letting Dust go first.

 

"You look delectable stuck in the wall like this Runix" Dust whispers as he pulls Runix' pants down seeing his magyk already summoned. Runix shivers in anticipation as Dust's member teases his ass before sinking in, Dust setting a fast pace leaving Runix gasping and gripping the wall as he moans loudly. Dust cums within Runix with a muffled curse right after Runix, Runix' own cum dripping down the wall.

 

Killer goes next, rubbing Runix' ass before thrusting in all the way hard in one go. Killer goes deep yet slow, drawing different kinds of moans from Runix as he takes his time bringing another orgasm out of their smallest mate, Runix' eye lights becoming hazier by the second. Killer cums hard causing Runix to seize up as he feels himself getting full with his mates' cum.

 

The next thing Runix feels against his ass is Horrors larger member breaching him the burn from the stretch leaving him breathless and keening for more. Horrors pace is more brutal than Dust or Killers being larger than the two of them in bulk despite only being slightly taller. Runix cums faster this time being oversensitive from his first few orgasms, Horrors claws digging into his ass as he cums in Runix who definitely feels full of his mates' cum now.

 

Cross gently caresses his ass before slowly entering, sending shivers up Runix' spine from the change of tempo with his gentle lovemaking pace that Runix audibly rattles with pleasure his eye lights hearts and tears falling down his skull. Runix comes with a soft cry, feeling Cross' cum drip from his thoroughly fucked ass as he shivered in anticipation knowing Error and Nightmare haven't had their turn yet.

 

Error takes his time, savoring every noise and whimper Runix makes as he fucks Runix slow, but not gently making every one count driving Runix steadily to his next orgasm. Error curses lowly as he cums, palming Runix' abused ass as his thrusts stutter fucking Runix through their orgasms the two having came at exactly the same time.

 

Runix shudders as Nightmares tentacles feel his swollen stomach, all of his mates' cum swirling inside except for Nightmares. Using his tentacles to spread Runix' legs wider, he seats himself fully within their smallest utilizing both his member and his tentacles to fuck Runix relentlessly. Runix sobs out as he cums hard, blacking out right after Nightmare comes with a grunt and a growl of a curse. He doesn't feel his date mates pull him out of the wall, clean him up or surround him in the bed they share, holding him as they all sleep. Runix laying across Nightmare and Error as the others pile up on each side of them.


	29. Day 29: Double-Penetration

**Summary for the Chapter:**

> Nightmare x Runix
> 
> Bonus: tentacles

"Hey, um, Nightmare?" Runix stammers, pulling his shirt down covering his pelvis with the end of his shirt and his tails. Nightmare sits up on the bed patting beside him waiting as Runix slowly makes his way to the side of the bed. Nightmare motions Runix to remove his hands, scared Runix complies revealing a dripping pussy with his ass instead of his usual member. "It...it won't dissipate. I've tried and everyone else isn't home" Runix stammers.

 

Nightmare lifts Runix into his lap with his tentacles, using two to spread the lips of Runix' pussy drawing a rather lewd moan from the smaller. Smirking, Nightmare lets one slowly slide in. "annnn Nnnniiiggghhhttttmmmaaarrreeee fffff s-so g-good" Runix moans lowly his eye sockets fluttering as his eye lights flicker. Nightmare quickly binds Runix in his tentacles hovering his mate into the air one teasing his ass while another playes with Runix' clit. 

 

"agggkgkkkkk N-nnng h-harder N-night!" Runix moans, bucking agianst Nightmares tentacles, feeling fuller than usual as Nightmares tentacle slides in his ass the other barely having the tip of the tentacle inside Runix' pussy. Runix grips hard onto the tentacles holding him as his pussy is slowly stretched and prepared his ass already being fucked relentlessly by one of Nightmares tentacles. He rattles in pleasure as he's lowered onto Nightmares cock, the tentacle in his ass still there.

 

"S-so f-full nnnn" Runix moans as he writhes in Nightmares hold cumming hard twice already, his pussy soaking wet from his own juices as Nightmare struggles not to cum too quickly. Nightmare growls, enjoying the sight of Runix practically fucking himself on his tentacles and member enjoying making Runix so full. Soon he'd make Runix full of his cum too, his smaller mate seems to be loving it so far with how much he's moaning and writhing under Nightmares touches.

 

Nightmare curses lowly as Runix cumes again, clenching hard enough around him to almost make him cum as well. Flipping Runix against the wall, Nightmare sets a brutal pace with his member and tentacle Runix lost to almost everything except for the mind-numbing pleasure-pain from his oversensitive magyk. Growling, Nightmare presses a phalange to Runix' clit harshly rubbing the sensitive nub of magyk.

 

Runix moans as he comes calling Nightmares name in a shuddering gasping breathy moan to the roof, his eye lights rolling to the back of his skull as he passes out the minute Nightmare finishes cumming deep in both holes. After cleaning Runix up, Nightmare tucks Runix in. Nightmare pulls his smaller mate to him as he reads a book watching over Runix as he sleeps, his magyk finally dissipated.

 

"You bonehead. If you wanted that you could've asked" Nightmare grumbles as he looks at Runix' sleeping face before turning back to his book a light blush on his otherwise impassive face. He'd tell the others about this later. For now, he'd make sure to watch over Runix until they returned not wanting another incident with Runix' horrible night terrors when the smaller sleeps alone.


	30. Day 30: Primal

**Summary for the Chapter:**

> Horror x Runix
> 
> go figure. 
> 
> let's have fun shell we?

yy"You ready, Runie?" Horror asks, the two had moved to the empty basement for this as they would probably threaten to destroy the house if they did this anywhere else. Nightmare and Error would have their head if they did this upstairs and destroyed something or hurt someone or themselves. The others are waiting in another room for them to finish to help with any injuries and give the two snacks and drinks as Runix and Horror would need them when they finish. Primal play takes a lot of energy and it wouldn't do for one of them to fall because of that so precautions had to be taken.

 

"Y-yeah. The safeword is xio" Runix stutters, feeling rather nervous about letting go to his more feral side. He didn't want to hurt Horror but he knew that the others would step in if they sensed one of them getting actually hurt during their session. Horror nods, his magyk gathering visibly across his naked scarred form as Horrors one eye light becomes slitted and he starts drooling red magyk. 

 

Runix lets his own do the same, growing slightly in size his legs going from regular skeletons to resembling a bipedular fox just without all the fur his tails swaying dangerously as he lets himself go to his more primal urges. The two circle one another, growling, snarling and drooling as they size one another up. Runix is the first to lunge, seemingly aiming to take out Horrors legs who simply jumps up over Runix. 

 

Runix yelps, jolting to the side to avoid Horror crashing on top of him and pinning him, turning sharply and lunging at Horror managing to pin him to the floor. The two struggle flipping position as to who is on top several times before separating again. Lunging at one another again, Runix and Horror scuffle going back and forth with who is pinning who until Horror manages to pin Runix by his throat with his teeth.

 

Runix fights back until Horror thrusts fully into him brutally fucking Runix against the floor, the only sounds in the room being pleasured growls, mewls, moans, growls and the sound of ecto flesh slapping together. Neither last long due to the energy spent fighting Horror cumming deep within Runix with a guttural growl as Runix cums clenching around him. Both pass out almost immediately after, the others returning once they have returned to normal.

 

Nightmare carried Horror while Error carries Runix as the others help clean the two and the room before Error and Nightmare settle them in the bed Runix immediately clinging to them in his sleep. Dust and Killer join the pile with Cross shortly after they make sure there is snacks and drinks available when Runix and Horror wake up. They all fall asleep listening to each other's soul beats, even the ones not exhausted from watching the display of power and force.


End file.
